Julienne the carrot, slice the onion, and cut the bell peppers into thin strips after removing seeds and stems.

Mix the marinade ingredients in a bowl and massage into the beef. Let it sit for 10 minutes.

Heat sesame oil in a frying pan over medium heat. Add the beef and onion, stir-frying until the beef changes color.

Add the carrot and stir-fry until softened. Then add the bean sprouts and bell peppers, cooking for another minute.